Elongate Flexible Torque Instruments And Methods Of Use

ABSTRACT

Torque shafts and other related systems and methods are described herein. In one embodiment, the torque shafts are both flexible and capable of transmitting torque. An apparatus for transmission of torque includes an elongate body, comprising a plurality of joint segments, each joint segment configured to pivot with respect to an adjacent segment and being further configured to have at least two link elements.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of PCT Application Serial No. PCT/US2007/071535, titled “Torque Shaft and Torque Drive”, filed on Jun. 19, 2007, which claims priority to U.S. Provisional Application Ser. No. 60/805,334, titled “Torque Shaft and Torque Drive”, filed on Jun. 20, 2006, each of which is incorporated herein by reference in its entirety for all purposes.

BACKGROUND OF THE INVENTION

1. Field

Embodiments of the present invention relate generally to elongate flexible instruments, and more particularly, to the manufacture and use of such elongate flexible instruments, which may be configured to be extension tools for a variety deployment, placement, installation, maintenance, repair, or removal type of functions, procedures, operations, or applications.

2. Background

Typical elongate flexible instruments may be comprised of flexible shafts, tubes, rods, etc., which may be susceptible to torque deflection or torque lag to the extent that rotation of one end of the instrument may not correlate closely to rotation of the opposite end of the instrument and substantial amount of wind-up or excessive amount of initial rotation or torque may be required at the outset before correlatable rotation or torque transmission could be achieved. In addition, elongate flexible instruments may be susceptible to buckling and/or kinking such that reliable torque transmission may be for practical purposes virtually impossible. Accordingly, there is a need for an elongate flexible instrument that allows improved transmission of rotation or torque.

BRIEF SUMMARY OF THE INVENTION

Various embodiments of an apparatus for transmission of torque are disclosed herein. In one variation, an apparatus for transmission of torque includes an elongate body, wherein said elongate body is comprised of a plurality of segments; each segment may be configured to flex or pivot with respect to an adjacent segment and each segment may include at least two link elements.

In one example, an apparatus for transmitting torque includes a plurality of joined segments in an axial arrangement, wherein each of said segments may be linked or joined to an adjacent segment by a living link element and the segments may be configured to flex or pivot about said living link element.

In another example, an apparatus for transmitting torque includes an elongate body, wherein said elongate body may be comprised of a plurality of joined segments. Each segment may be configured to flex or pivot with respect to an adjacent segment and each segment may be configured to have a pair of link elements. Each link element may include a hub and a plurality of living link elements extending from said hub that may be coupled to a rim of an adjacent segment.

An exemplary embodiment of a method for operating an apparatus for transmitting torque is disclosed, which may be applicable to any or all of the apparatuses as described in accordance with embodiments of the present invention disclosed herein. The method may include attaching a medical prosthesis at a distal end of said torque transmitting apparatus, inserting said prosthesis into a patient's vasculature, navigating within said patient's vasculature, and deploying said medical prosthesis at a target region.

Other systems, methods, features, and advantages of the present invention will be apparent to one of ordinary skill in the art upon examination of the following figures and detailed description. It is intended that all such additional systems, methods, features, and advantages be within the scope of the present invention. It is also intended that the present invention is not limited to the specific details of the exemplary embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

The details of the invention, both as to its structure and operation, may be gleaned in part by study of the accompanying figures, in which like reference numerals refer to like parts. The components in the figures are not necessarily drawn to scale; instead emphasis is placed upon illustrating the principles of the invention. Moreover, all illustrations are intended to convey concepts, where relative sizes, shapes and other detailed attributes may be illustrated schematically rather than literally or precisely.

FIG. 1 illustrates an elongate flexible torque instrument in accordance with one embodiment of the present invention.

FIG. 2A illustrates a portion of a flexible torque member in accordance with one embodiment of the present invention.

FIG. 2B illustrates a portion of a flexible torque member in accordance with one embodiment of the present invention.

FIG. 3 illustrates a portion of another flexible torque member in accordance with one embodiment of the present invention.

FIG. 4 illustrates the interface of physical link element or splink link element and torque link element or torque finger element for one exemplary embodiment of torque shaft (400) in a planar depiction.

FIG. 5 depicts a torque shaft with splink link and torque finger interlocking elements according to another embodiment.

FIG. 6A illustrates a side view of a torque shaft with a wagon wheel link element according to another embodiment of the present invention.

FIG. 6B illustrates an isometric view of the same torque shaft.

FIG. 7 illustrates one example of an interface or implementation of flexible torque members with an implant deployment apparatus in accordance with one embodiment of the present invention.

FIGS. 8A-8C show a torque shaft with T-shaped interlocking features according to an embodiment.

FIGS. 9A-9B show a torque shaft with teardrop shaped interlocking features according to another embodiment.

FIG. 10 illustrates the torque transferring capability of the torque shaft.

FIG. 11 shows a torque shaft with spiral slots running the length of the torque shaft.

FIGS. 12-13 show a spot-link torque shaft according to another embodiment.

FIG. 14 shows a torque shaft with living hinges according to another embodiment.

FIGS. 15-16 show two opposing torque shafts according to another embodiment.

FIG. 17 shows a pull-pull torque drive according to another embodiment.

FIG. 18 shows a device for translating axial force applied to the shaft into rotational movement of the shaft.

FIG. 19A illustrates an example of an elongate flexible torque instrument being used to deliver an implant to a target site inside a patient in accordance with one embodiment of the present invention.

FIG. 19B illustrates an example elongate flexible torque instrument being used in an antegrade approach to deliver an implant to a target site inside a patient.

FIG. 19C illustrates a process flowchart for using the elongate flexible torque instrument to deliver and deploy an implant in accordance with one embodiment of the present invention.

FIG. 19D illustrates an example elongate flexible torque instrument being used in a retrograde approach to deliver an implant to a target site inside a patient.

DETAILED DESCRIPTION

Elongate flexible torque instruments and methods for their use and manufacture are described herein. The elongate flexible torque instruments in accordance with embodiments of the present invention may be both flexible and stiff at the same time. In one embodiment, the elongate flexible torque instruments according to the present invention are designed and manufactured to be substantially flexible for pivoting, steering, bending, etc., but substantially stiff in resisting rotation and axial compression or extension such that they may effectively transmit rotation or torque and axial forces, loads, movements, etc., while it may be pushed, pulled, advanced, retracted, navigated, steered, bent, twisted, or contorted into various positions, shapes, orientations, and/or tight curvatures along tortuous pathways. The functional characteristics of the elongate flexible torque instruments as described herein are particularly suited as extension tools for deployment, placement, installation, maintenance, repair, or removal type of functions, procedures, operations, or applications. In particular, the elongate flexible torque instruments may be well suited as extension tools for performing various minimally invasive surgical procedures, e.g., deploying, placing, installing, or removing implants (e.g., prosthetic heart valves) inside a patient. For example, in a minimally invasive surgical procedure an implant may be delivered to a target site in a patient through a percutaneous incision or natural body orifice using one or more elongate flexible torque instruments by way of the patient's vasculature or natural body pathways (such vasculature and natural body pathways may be tortuous and less than 1 cm in diameter) to various organs (e.g., heart, stomach, bladder, uterus, etc.), or tissue structures.

FIG. 1 illustrates an elongate flexible torque instrument in accordance with one embodiment of the present invention, which may be used as an extension tool to deliver an implant in minimally invasive surgical procedures. As illustrated in FIG. 1, the elongate flexible torque instrument (100) includes an elongate body (102) that may be manually pushed, advanced, steered, and/or rotated. The elongate body (102) may have an outer diameter in the range of about 1.5 French to about 30 French—in the French catheter scale. In some embodiments, the elongate body (102) may have an outer diameter in the range of about 20 French to about 30 French. In other embodiments, the elongate body (102) may have an outer diameter in the range of about 10 French to about 20 French. In certain applications, the elongate body (102) may have an outer diameter of about 11 French or about 12 French. In certain other applications, the elongate body (102) may have an outer diameter of about 9 French, about 8 French, about 7 French, or about 6 French.

Handle (104) includes a control lever (106) that may operate one or more control wires or pull wires to steer the distal portion of the elongate body (102) as the elongate body is pushed or advanced through various tortuous natural body pathways. The use of control wires or pull wires to steer an elongate body has been previous described in various systems (e.g., a sheath member or a guide member of a manually steerable catheter). Examples of such steerable systems are disclosed U.S. patent application Ser. No. 11/073,363, titled “Robotic Catheter System”, filed on Mar. 4, 2005; and U.S. patent application Ser. No. 11/481,433, titled “Robotic Catheter System and Methods”, filed on Jul. 3, 2006. In addition, a first control knob (108) and a second control knob (110) may be manually operated to rotate elements or components of the elongate body (102), such that rotation or torque applied at the first control knob (108) and/or second control knob (110), either separately or in concert, transmits rotation or torque from the proximal portion of the elongate body (102) to the distal portion of the elongate body (102).

The elongate body (102) and elements of the elongate body (102) may be designed and manufactured to be substantially stiff for torsional applications, such that there is minimum amount of torque deflection or torque lag from one section (e.g., the proximal section) of the elongate body or elements of the elongate body to another section (e.g., the distal section) of the elongate body or elements of the elongate body. At the same time, the elongate body (102) or elements of the elongate body (102) may also be designed and manufactured to be substantially flexible, so that the elongate body (102) may be steered, pivoted, or deflected in various directions (e.g., up, down, pitch, yaw, etc.) as well as bent or displaced into various positions, shapes, and/or tight curvatures (e.g., a J-bend or a J-shaped bend). In addition, for certain applications the elongate body (102) may be able to neutrally maintain complex shapes and tight curvatures. For example, no particular control or force may be necessary to maintain the elongate body (102) in certain complex shapes or tight curvatures. As will be explained in further detail, the elongate body (102) is comprised of segments that are substantially free to flex, bend, or pivot, such that that is no substantial resistance, inertia, or inherent shape memory properties to return or restore the elongate body (102) to a certain disposition, orientation, or shape.

In addition, the elongate body (102) may be operatively coupled to a delivery mechanism (112) to deliver an implant, such as a prosthetic heart valve. The delivery mechanism (112) may be similar to the deployment mechanism described in U.S. patent application Ser. No. 11/364,715, titled “Methods And Devices For Delivery Of Prosthetic Heart Valves And Other Prosthetics”, filed on Feb. 27, 2006; and U.S. patent application Ser. No. 11/364,724, titled “Methods And Devices For Delivery Of Prosthetic Heart Valves And Other Prosthetics”, filed on Feb. 27, 2006, which are both incorporated herein by reference in their entirety for all purposes. The elongate flexible torque instrument (100) along with the delivery mechanism (112) or similar delivery mechanisms (such as those described in the aforementioned patent applications) may be used to deliver an implant, such as a prosthetic heart valve, which may be similar to those described in U.S. patent application Ser. No. 11/066,124, titled “Prosthetic Heart Valves, Scaffolding Structures, And Systems and Methods For Implantation of Same”, filed on Feb. 25, 2005; U.S. patent application Ser. No. 11/066,126, titled “Prosthetic Heart Valves, Scaffolding Structures, And Systems and Methods For Implantation of Same”, filed on Feb. 25, 2005; and U.S. patent application Ser. No. 11/067,330, titled “Prosthetic Heart Valves, Scaffolding Structures, And Systems and Methods For Implantation of Same”, filed on Feb. 25, 2005; these patent applications are all incorporated herein by reference in their entirety for all purposes.

FIG. 2A illustrates a portion or section of an elongate flexible torque member (200) in accordance with one embodiment of the present invention, which may be one of the elements or components of the elongate body (102). The flexible torque member (200) may be fabricated from a tube or shaft made from any suitable material for the function, procedure, operation, or application for which the elongate flexible torque instrument may be used. As one of ordinary skill in the art having the benefit of this disclosure will appreciate, the flexible torque member (200) may be fabricated from a rod or other elongate structure other than a tube or shaft. Accordingly, in some embodiments, the flexible torque member (200) may include a lumen; while in some other embodiments, the flexible torque member (200) may not include a lumen. For some embodiments, the elongate flexible torque instrument (100) may be used for minimally invasive surgical procedures; as such the flexible torque member (200) may be fabricated from a tube, shaft, rod, or other elongate structure made of any biologically compatible material, e.g., stainless steel, Nitinol, other alloy or non-alloy material. The fabrication process may include cutting the tube, shaft, rod, or other elongate structure into a plurality of segment members; such as first segment members (202 a) and second segment members (202 b), as illustrated in FIG. 2A.

In addition, various elements, features, or patterns may be cut into the segment members, such that the finished flexible torque member (200) comprised of the segment members (202 a and 202 b) may be both substantially flexible (e.g., flexible for steering movements or deflection, such as up, down, pitch, yaw, etc.) and substantially stiff (e.g., stiff for torsion, twist, and axial extension and compression, etc.). The plurality of segment members (202 a and 202 b) of the flexible torque member (200) may be physically linked. That is, as illustrated in this example, the segment members (202 a and 202 b) may not be completely circumferentially cut into separate or individual pieces or segments; instead they may be physically linked together (for example by a live link or living link (204 c), as illustrated by the material between the first link element (204 a) and second link element (204 b)) as a one piece unit. In other embodiments of the present invention, however, the segment members (202 a and 202 b) may be completely circumferentially cut into separate or individual pieces or segments. For those segments (202 a and 202 b) that are completely circumferentially cut into separate or individual pieces, they may be linked or joined together by fitting or interlocking the separate or individual segments (202 a and 202 b) together; similar to fitting or interlocking pieces of puzzles together. The separate or individual segments (202 a and 202 b) may be fitted together by way of the elements, features, or patterns that may have been cut into one or more pivotal link elements (not shown) of the segment members; similar to the physical link elements but completely circumferentially cut.

FIG. 2A illustrates one embodiment of elements, features, or patterns that may be cut into the segment members (202 a and 202 b). As may be appreciated, the geometries of the elements, features, or patterns may be any shape and/or size that would facilitate the fitting or interlocking the first and second segments (202 a and 202 b). The linking, fitting, or joining of the separate and individual first and second pieces or segments (202 a and 202 b) may be further facilitated or made more secured by having the mating segments cut at various angles (α), as illustrated in FIG. 2B, so that the segments (202 a and 202 b) may be fitted or interlocked together more securely to reduce the chances for the segments (202 a and 202 b) to separate or the flexible torque member (200) falling apart into pieces of segments (202 a and 202 b).

In some embodiments, the segments may be cut at cut angle in range between about 0 degree and about 90 degrees substantially about the periphery of the features of the segments. In some particular embodiments, the segments may be cut at cut angle (α) in the range between about 0 degree and about 30 degrees substantially about the periphery of the features of the segments. In other embodiments, the segments may be cut at cut angle (α) in the range between about 30 degrees and about 45 degrees substantially about the periphery of the features of the segments. In other particular embodiments, the segments may be cut at cut angle (α) in the range between about 45 degrees and about 60 degrees substantially about the periphery of the features of the segments. In further particular embodiments, the segments may be cut at cut angle (α) in the range between about 60 degrees and about 90 degrees substantially about the periphery of the features of the segments.

In some embodiments, the flexible torque member (200) may be encapsulated by a flexible membrane sheath to maintain the individual and separate pieces of segments together. The flexible torque member (200) may be made from a tube, shaft, rod, or other elongate structure, which may be cut by moving and turning the tube, shaft, rod, or other elongate structure across a cutting tool to cut out the mating or interlocking segments (202 a and 202 b) as well as the particular elements, features, or patterns that may help the segments (202 a and 202 b) fit, mate, or interlock together. The cutting tool may be manually controlled or computer controlled (e.g., a computer controlled laser cutting tool) cutting system. In addition, the segments (202 a and 202 b) as well as the particular elements, features, or patterns may be cut at prescribed cut angles (α) as discussed to further provide secure fitting or interlocking of the segments (202 a and 202 b) into one unit making up the flexible torque member (200). The cutting process may remove a portion of the tube, shaft, rod, or other elongate structure so as to leave open spaces or gaps between first and second segments (202 a and 202 b). The width of these spaces or gaps may be substantially large enough to allow adjacent segments (202 a and 202 b) to move, flex, pivot, or bend at various angles relative to each other. For example, the larger the space or gap between the first and second segments (202 a and 202 b), the greater the relative movement, flex, pivot, or bend may be possible between adjacent segments (202 a and 202 b).

Still referring to FIG. 2A, first and second segments (202 a and 202 b) of the flexible torque member (200) include mating or interlocking geometries of physical link elements (204 a and 204 b) and torque link elements (206 a and 206 b). In this example, physical link elements (204 a and 204 b) include live link or living link elements (204 c) in which the first and second segments (202 a and 202 b) are physically linked together, such that the flexible torque member (200) is one continuously and physically linked member. In other embodiments, the physical link elements (204 a and 204 b) may not include a live link or living link element, such that the flexible torque member (200) is not one continuously and physically linked member. Instead, the flexible torque member (200) is comprised of fitted or interlocked separate and individual segments (202 a and 202 b). The physical link elements (204 a and 204 b) allow the segments (202 a and 202 b) to flex, pivot, or bend relative to each other, such that the flexible torque member (200) may be steered in various directions or displacements, e.g., up, down, sideways, pitch, yaw, etc. In addition, the torque link elements (206 a and 206 b) includes torque fingers (206 c) that may provide torsional or rotational support or rigidity to the fitted, mated, contacted, or interlocked segments (202 a and 202 b), such that the flexible torque member (200) is flexible, e.g., up, down, sideways, pitch, yaw, etc., but also torsionally stiff against rotation, twist, torque, etc.

FIG. 3 illustrates a portion or section of another flexible torque member (300), in accordance with one embodiment of the present invention, including one embodiment of a physical link element (304) and one embodiment of torque link element (306). The flexibility of the flexible torque member (300) per unit length may be dependent upon the amount of flex, bend, or pivot between adjacent segments (302 a, 302 b, 302 c, etc.) relative to each other. Since the amount that adjacent segments (302 a, 302 b, 302 c, etc.) may be able to flex, bend, or pivot may be determined by the space or gap between the segments, e.g., space or gap (410) illustrated in FIG. 4, the overall flexibility of the torque member (300) per unit length may be determined or characterized by the width of the space or gap (410) and the number of segments (302 a, 302 b, 302 c, etc.) per unit length.

The physical link element (304) and torque link element (306) allow the flexible torque member (300) to be flexible while enabling the torque member (300) the ability to transmit torque that is applied at one end of the torque member (300) to the other end of the torque member (300). As the flexible torque member (300) is rotated about its longitudinal axis, as illustrated in FIG. 3 by the directions indicated by the arrow, the link elements (304 and 306) may transfer or transmit torsional force longitudinally along the length of the torque member (200), at which point torque may be transferred or transmitted between the adjacent segments (302 a, 302 b, 302 c, etc.) along the length of the flexible torque member (300).

Looking more closely at FIG. 3, each physical link element (304) may include two strut elements (310) that may substantially surround a living link element (308). A living link element (308) may be considered as an element that provides a physical link between two member components. In this example, the living link element (308) provides a physical link between a first segment (302 a) and a second segment (302 b). Similarly, the living link element (308) also provides a physical link between a second segment (302 b) and a third segment (302 c). Such physical linkages may continue on with many segments of a flexible torque member. The strut elements (310) may have circular shapes or any suitable geometrical shapes and may be configured to pivot within a space, gap, or slot (312), which may have corresponding or mating shapes to the strut element (310) for receiving, matching, mating with the strut elements (310), so that adjacent segment (e.g., 302 a and 302 b or 302 b and 302 c) may flex, bend, pivot, etc. relative to one another. This combination of physical link elements or configuration may be referred to as a splink link element since it is composed of the combination of a spot link and a living link (as described in full in PCT Application Serial No. PCT/US2007/071535). Accordingly, in this example, a splink element or splink link element (304) may be collectively comprises a living link element (308), strut elements (310), the space, gap, or slot (312) between adjacent segment members (302 a, 302 b, 302 c, etc.) of a flexible torque member (300).

Still referring to FIG. 3, each segment (302 a, 302 b, 302 c, etc.) may also include torque link elements (306). A torque link element (306) may include a male element (314) and a female element (16). As illustrated in FIG. 3, a male element (314) of one segment member (e.g., 302 a) mates with or fits into a female element (316) of an adjacent segment member (e.g., 302 b). The combination of mating or fitting of the male element (314) into the female element (316) in no way affects the flexing, bending, or pivoting or adjacent segments (e.g., between segment 302 a and 302 b, and between segment 302 b and segment 302 c, etc.) as allowed by the physical link element (304). The amount of flex, bend, or pivot between two adjacent segment members is defined or characterized by the amount of space or gap (e.g., space or gap (402)) between the adjacent members as previously described. Each female element 316 preferably receives the male element 314 in relative or substantial tight confines so as to allow movement in an axial direction but not rotational, although minimal rotational movement may occur. The described torque link 306 may be referred collectively as torque finger element 306.

Referring again to FIG. 3, in some embodiments to increase the flexibility of the torque member (300), the physical link elements (304) or splink link elements (304) and the torque link elements (306) or torque finger elements (306) may be oriented or disposed at about 90 degrees with respect to each other. This may be done to enable the interlocking or link elements 304 and 306 to hold or support the segments (e.g., 302 a, 302 b, and 302 c) together; such that the flex, bend, or pivot axes of the segments (302 a, 302 b, and 302 c) may be alternated between two perpendicular axes. For example, as illustrated in FIG. 3, the pivot axis (331) of adjacent segments (302 a and 302 b) is perpendicular to the pivot axis (332) of adjacent segments (302 b and 302 c). The alternating pivot axes allow the torque member (300) to flex, bend, or pivot in variety of directions as well as definable ranges about each axis. Each pair of interlocking or linking elements (304 and 306) transmits torque between the corresponding adjacent segments (302 a, 302 b, and 302 c) when the torque member (300) is rotated along its longitudinal axis. In addition, the linking elements (304 and 306) may also provide column strength (e.g., compressive and tensile strength) to the torque member (300), such that the torque member (300) may have necessary column strength or integrity to be pushed or advanced as well as pulled or retracted. For example, the flexible torque member (300) may be pushed or advanced as well as pulled or retracted along vasculatures or natural tortuous pathways inside a patient. Accordingly, the elongate body (102) of an elongate flexible torque instrument (100), which may be constructed in part by one or more torque members, has the flexibility for flexing, bending, or pivoting and the stiffness to transfer or transmit twist, rotation, and torque as well as the structural strength and integrity to be pushed or advanced and pulled or retracted along vasculatures or natural body pathways inside a patient.

Still referring to FIG. 3, in some embodiments, the physical link elements (304) or splink link elements (304) of one segment (302 a, 302 b, 302 c) may be oriented or disposed at about 180 degrees with respect to each other. Similarly, in some embodiments, the torque link elements (306) or torque finger elements (306) of one segment (302 a, 302 b, 302 c) may be oriented or disposed at about 180 degrees with respect to each other. While in some embodiments, the physical link elements (304) or splink link elements (304) of adjacent segments (302 a, 302 b, 302 c) may be oriented or disposed at about 90 degrees with respect to each other. Similarly, in some embodiments, the torque link elements (306) or torque finger elements (306) of adjacent segments (302 a, 302 b, 302 c) may be oriented or disposed at about 90 degrees with respect to each other.

The flexible torque member (300) may include optional guides for steering cables (not shown) for steering the flexible torque member. For example, the torque member (300) may comprise four equally spaced guides along its inner surface for receiving four steering cables. Alternatively, the guides may also be on the outer surface of the torque member.

One advantage of the splink link configuration described above is the fact that the torque shaft (300) requires minimal, if any, rotation of the shaft at a proximal end before torque is transmitted to the distal end. Before torque can be transmitted from one end of a torque member (300) to the other end, the rotational slack between each one of the adjacent sections or segments (302 a, 302 b, 302 c) of the shaft (300), if any, must be removed by rotating the shaft (300). The minimization or entire elimination of rotational slack allows an operator of the shaft (300) an increased level of control and precision in guiding the shaft (300) during delicate medical procedures.

FIG. 4 illustrates the interface of physical link element or splink link element and torque link element or torque finger element for one exemplary embodiment of torque shaft (400) in a planar depiction. The planar depiction as illustrated in FIG. 4 shows the link patterns for the link elements might be cut into the circumference of a tube, shaft, or any suitable elongate structure (for some application, a rod or other solid elongate structure may be used) so as to form the torque member (400). As shown, the torque shaft (400) comprises a plurality of sections or segments (402 a, 402 b, and 402 c) physically connected together by living hinges (404). Adjacent segments (402 a, 402 b, and 402 c) are connected to each other by a pair of living hinges (404) located approximately 180 degrees from each other about the circumference of the torque shaft or torque member (400). Refer to FIG. 2 and FIG. 3 for isometric or three-dimensional depiction of a torque member for clarification of the spatial relationship between the link elements. The segments (402 a, 402 b, 402 c) may be cut from a tube, shaft, or any other suitable elongate structure, in which thin portions of the tube may be left connected between the segments (402 a, 402 b, 402 c) to form the living hinges (404). The struts (408); space, gap, or slot (410); and the male/female torque finger elements (412, 414) may also be similarly formed in the configuration as depicted in FIG. 4. Preferably, the stock tube, shaft, rod, or any suitable elongate structure of which the torque member (400) is made from may be made of a pliable material, metal, or plastic, e.g., NITINOL (or other NiTi alloy), stainless steel, MP35N alloy, or Polyetheretherketone (PEEK), Elgiloy, or any other pliable material that enables the living hinges to flex, bend, or pivot with the desired level of durability or resistance to fatigue or without plastic deformation.

In some embodiments, spaces, gaps, or slots (410) may be cut on both sides of each living hinge element (404) to increase the length of the hinge element (404) to increase the amount movement that each hinge element may be able to flex, bend, or pivot. The living hinge elements (404) allow adjacent segments (402 a, 402 b, 402 c) to flex, bend, or pivot relative to each. In some embodiments, wedge-shaped portions of the elongate structure may be cut away between adjacent segments to provide the necessary spaces or gaps (410) such that adjacent segments may be able to flex, bend, or pivot relative to each other. Adjacent pairs of living hinge elements (404) may be orientated at approximately 90 degrees from each other. For example, as illustrated in FIG. 4, the living hinge elements (404) between adjacent segments (402 a) and (402 b) are orientated at about 90 degrees with respect to each other. The 90 degree orientation between adjacent pairs of living hinge elements (404), when used on a torque shaft (400) having a relatively large number of segments (402 a, 402 b, 402 c, etc.), allows the torque shaft (400) to flex, bend, or pivot in a substantially smooth, fluid, or substantially unencumbered manner in various directions, e.g., X, Y, and Z directions.

Referring back to torque finger elements (314) of FIG. 3, each pair of male torque finger elements (314) extends from a segment (302) and is received in a pair of corresponding female torque elements (316) of an adjacent segment (302). To allow adjacent segments (302 a, 302 b, 302 c) to bend about the hinge elements (308), the female torque elements (316) are dimensioned so that the corresponding torque finger elements (314) may slide in and out of the female torque elements (316) to allow the adjacent segments (302 a, 302 b, 302 c) to flex, bend, and pivot about the link elements (304). The torque finger elements (314), in conjunction with the living hinge arrangement (304) described above, transmit torque between adjacent segments (302 a, 302 b, 302 c) of the shaft (300) when the shaft is rotated about its longitudinal axis by pushing against the side walls of the corresponding female torque elements (316).

FIG. 5 depicts a torque shaft with splink link and torque finger interlocking elements according to another embodiment. In this embodiment, the torque shaft (500) includes the torque finger element (510) and corresponding female torque element (512) similar to the discussion as described above, however, the splink link element (502) is substantially rectangular-shaped with radiused contact surfaces as opposed to the substantially oval or teardrop-shaped physical link element as illustrated in FIG. 2, FIG. 3, and FIG. 4. As one of ordinary skill in the art may appreciate, the geometrical construct of the splink-link element may be varied without deviating from the inventive scope of the disclosed embodiments of the present invention. In this embodiment, the living link (506) is manufactured so that there are two substantially curved male elements (508) surrounding the living link (506) on either side. The space, gap, or slot (514) permits the adjacent segments to pivot in relation to each other and allow the overall elongate structure or torque member (500) the ability to flex, bend, or pivot in a substantially fluid manner in various directions, e.g., X, Y, and Z directions.

FIG. 6A illustrates a side view of a torque shaft (600) with a wagon wheel link element (602) according to another embodiment of the present invention. FIG. 6B illustrates an isometric view of the same torque shaft (600). Here, the torque shaft (600) may be laser cut in order to leave a “wagon-wheel” design that couples a plurality of segments (612 a, 612 b, 612 c). As one of ordinary skill in the art having the benefit of this disclosure would appreciate, this embodiment provides similar benefits to the torque shaft construction previously discussed but uses a series or plurality of living links to accomplish the task. As shown, each of the segments (612 a, 612 b, 612 c) has a pair of wagon wheel link elements (602) at substantially opposite portions of each segment (612). The adjacent segment (612) will have a pair of wagon wheel link elements (602) at about 90 degrees offset so as to facilitate the flexible movement of adjacent segments (612 a, 612 b, 612 c).

Each wagon wheel link element (612) may include a hub portion (604) and a plurality of living link elements or “spoke” elements (606) extending from the hub (604) to rim elements (610) of an adjacent segment (612). The degree of flexibility in this embodiment may be affected by either the size of the spaces or gaps (608) and/or the length of the spoke elements (606). In order to compensate for the length needed during a compression or an operation cycle of the spokes (606), i.e., to allow the lengthening needed for turning of the pivot, the spoke elements (606) may have a slight elbow bend. In other words, the spoke elements may be “L-shaped”, which may resemble the shape of an elbow. The length, width, height, shape, orientation and number of the spokes (606) may be tailored for a multitude of applications depending on its intended use, i.e., modifications can vary the stiffness of the torque member (600) and its axial/torsional strength. In another embodiment, the L-shaped spoke structure element of the splink link element may be implemented on a torque shaft (600) in combination with the torque finger elements, as previously described, to provide a flexible shaft with torque transmission capability.

FIG. 7 illustrates one example of an interface or implementation of flexible torque members with an implant deployment apparatus in accordance with one embodiment of the present invention. FIG. 7 illustrates an example of an implant deployment device (702), which may be substantially similar to the deployment mechanism described in U.S. patent application Ser. No. 11/364,715, titled “Methods And Devices For Delivery Of Prosthetic Heart Valves And Other Prosthetics”, filed on Feb. 27, 2006; and U.S. patent application Ser. No. 11/364,724, titled “Methods And Devices For Delivery Of Prosthetic Heart Valves And Other Prosthetics”, filed on Feb. 27, 2006, which have been incorporated by reference in their entirety for all purposes. Flexible torque members (704 and 706) are operatively coupled to deployment device (702). For example, the flexible torque member 704 may be coupled to the wrapping pin hub (708) and flexible torque member 706 may be coupled to the slotted tube (710). The flexible torque members (704 and 706) may apply torque to the wrapping pin hub (708) and the slotted tube (710) to operate the deployment device (702) for deploying and/or releasing an implant or a prosthetic device. A prosthetic device may be similar to those described in U.S. patent application Ser. No. 11/066,124, titled “Prosthetic Heart Valves, Scaffolding Structures, And Systems and Methods For Implantation of Same”, filed on Feb. 25, 2005; U.S. patent application Ser. No. 11/066,126, titled “Prosthetic Heart Valves, Scaffolding Structures, And Systems and Methods For Implantation of Same”, filed on Feb. 25, 2005; and U.S. patent application Ser. No. 11/067,330, titled “Prosthetic Heart Valves, Scaffolding Structures, And Systems and Methods For Implantation of Same”, filed on Feb. 25, 2005; which all have been incorporated by reference in their entirety for all purposes. In some embodiments, the flexible torque members (704 and 706) may co-axially aligned and they may provide counter-acting torque, counter-rotating torque, or opposing torque to operate the wrapping pin hub (708) and the slotted tube (710) to deploy an implant or prosthetic device contained in the deployment device (702).

FIGS. 8A-8C show a torque shaft (800) according to an embodiment of the invention. The torque shaft (800) comprises a plurality of interlocking sections (812) cut into a steel tube. Some interlocking sections (812) may have different dimensions, e.g., one interlocking section (812) may longer (length measured in an axial direction) than another interlocking section (812), while other interlocking sections (812) may have substantially the same or similar dimensions. The sections (812) are linked together by interlocking geometry of slots (815). Each interlocking slot (815) extends around the circumference of the tube and comprises a plurality of interlocking features (820). The interlocking features (820) of each slot (815) connect two adjacent sections (812) on opposite sides of the slot (815). FIG. 8B shows an expanded view of one of the slots (815) and FIG. 8C shows an expanded perspective view of one of the slots (815). In this embodiment, each slot comprises T-shaped interlocking features (820). In broader terms, the male feature may be described as having a base and an end, and the end has a width or height that is greater than the base. FIGS. 9A-9B show a torque shaft (900) according to another embodiment, in which each slot (915) comprises teardrop-shaped interlocking features (920). The geometry of the interlocking features can be any shape that interlocks.

In the preferred embodiment, the torque shaft may be fabricated by laser cutting the slots into a steel tube. This may be done by moving the steel tube across a stationary laser under computer control to precisely cut the slots. Laser cutting is well known in the art for fabricating, e.g., stents.

Turning to FIGS. 8B and 9B, each of the slots (815, 915) has a width W defined by the width of the laser cut. The slot width W creates space between adjacent sections that allow adjacent sections (812, 912) to move slightly relative to each other. This movement allows adjacent sections (812, 912) to bend at a slight angle (e.g., 1-2 degrees) relative to each other. The larger the slot width W, the more adjacent sections (812, 912) can move, bend, or pivot relative to each other.

The flexibility of the shafts (800, 900) per unit length L depends on the amount that adjacent sections (812, 912) can bend relative to each other and the number of slots (815, 915) per unit length L. Since the amount that adjacent sections (812, 912) can flex, bend, or pivot is determined by the slot width W, the flexibility of the shafts (800, 900) per unit length is determined by the slot width W and the number of slots (815, 915) per unit length L. The flexibility of the shafts (800, 900) is approximately independent of the shape of the interconnecting features of the slots.

The interlocking slots (815, 915) allow the shafts (800, 900) to be flexible while allowing the shafts (800, 900) to transmit torque applied at one end of the shaft to the other end of the shaft. The torque transferring capability of the shaft (800) is illustrated in FIG. 10, which shows an expanded view of two adjacent interlocking features (820) of a slot (815). As the shaft 800 is rotated about it longitudinal axis in the direction indicated by the arrow, the adjacent interlocking features (820) of the slot (815) engage each other, at which point torque is transferred between the adjacent sections (812) of the slot (815).

FIG. 11 shows an interlocking slot (1115) according to another embodiment. In this embodiment, instead of a plurality of separate interlocking slots along the shaft, a continuous spiral or helical slot (1115) runs along the length of the shaft (1100). Alternatively, two or more helical slots may run along the length of the shaft. FIG. 11 also shows an example in which two contiguous interspaced helical slots (1125) and (1135) run along the length of the shaft (1110) next to each other. The helical slots may have the same interlocking geometry or different interlocking geometries.

FIGS. 12-13 show a spot-link torque shaft (1200) according to another embodiment of the invention. The torque shaft (1200) comprises a plurality of interlocking sections (1212). Each section (1212) comprises two male interlocking features (1215) on opposite sides of the section, and two female interlocking features (1217) on opposite sides of the section and orientated about 90 degrees with respect to the male interlocking features (1215). The male interlocking features (1215) have substantially circular shapes and the female interlocking features (1217) have corresponding substantially inwardly curved shapes for receiving the male interlocking features (1215) therein. The male interlocking features (1215) of each section (1212) fit into the female interlocking features (1217) of an adjacent section (1212). This fit enables adjacent sections (1212) to pivot relative to each other about an axis. Each female interlocking feature (1217) curves around the corresponding male interlocking feature (1215) may be more than 180 degrees to prevent adjacent sections (1212) from being pulled apart.

To provide space for adjacent sections (1212) to pivot, portions of the tube forming the shaft are removed or cut away between the adjacent sections. In this embodiment, wedge-shaped portions of the tube are cut away between adjacent sections to provide pivot spaces (1220). The pivot spaces (1220) between adjacent sections allow adjacent sections (1212) to pivot, e.g., 0-15 degrees, relative to each other.

The male interlocking features (1215) of adjacent sections (1212) are orientated at about 90 degrees from each other. This is done to enable the interlocking features to hold the sections together. This is also done so that the pivot axes of the sections alternate (1212) between two perpendicular axes. For example, in FIG. 13, the pivot axis of adjacent sections (1212 a) and (1212 b) is substantially perpendicular to the pivot axis of adjacent sections (1212 a) and (1212 c). The alternating pivot axes allow the torque shaft (1200) to flex, bend, or pivot in relatively unlimited directions about the axes.

The male interlocking features (1215) also enable the torque shaft (1200) to transmit torque from one end of the shaft to the other end of the shaft. Each pair of male interlocking features (1215) transmits torque between the corresponding adjacent sections (1212) when the shaft is rotated along its longitudinal axis. In addition, the interlocking features (1215) also provide column strength (compressive) and tensile strength to the shaft (1200).

The torque shaft may include optional guides for steering cables. FIG. 12 shows an example in which the torque shaft (1200) comprises four substantially equally spaced guides (1240) along its inner surface for receiving four steering cables. The guides may also be on the outer surface of the torque shaft.

The spot-link torque shaft has several advantages over the torque shaft with interlocking slots. One advantage is that adjacent sections of the spot-link torque shaft are able to pivot or bend to a much greater degree than adjacent sections of the torque shaft with interlocking slots. As a result, the spot-link torque shaft requires far fewer sections per unit length to flex or bend a given amount per unit length than the torque shaft with interlocking slots. This reduction in the number of sections reduces the amount of cutting required to fabricate the spot-link torque shaft compared to the torque shaft with interlocking slots.

Another advantage is that the spot-link torque shaft requires less rotation of the shaft before torque is transmitted from one end of the shaft to the other end of the shaft. Before torque can be transmitted from one end of a torque shaft to the other end, the rotational slack between each one of the adjacent sections of the shaft must be removed by rotating the shaft. Because the spot-link torque shaft has fewer sections than the torque shaft with interlocking slots, the spot-link torque shaft has less rotational slack that needs to be removed before toque is transmitted from one end of the shaft to the other end.

FIG. 14 shows a torque shaft (1400) according to another embodiment. The torque shaft (1400) comprises a plurality of sections (1412 a, 1412 b, 1412 c, etc.) connected together by living hinges (1415). Adjacent sections (1412 a, 1412 b, 1412 c, etc.) are connected to each other by a pair of living hinges (1415) on opposite sides of the shaft (1400). The sections (1412 a, 1412 b, 1412 c, etc.) are laser cut into a tube, in which thin portions of the tube are left connected between the sections (1412 a, 1412 b, 1412 c, etc.) to form the living hinges (1415). Preferably, the tube is made of a pliable metal, e.g., steel or Nitinol, or other pliable material that enables the living hinges to flex or bend without breaking. Slots (1417) are cut on both side of each living hinge (1415) to increase the length of the hinge (1415) and hence the amount that each hinge can bend. The living hinges (1415) enable adjacent sections (1412) to flex, bend, or pivot relative to each other. To provide space for adjacent section (1412 a, 1412 b, 1412 c, etc.) to bend, portions of the tube are removed or cut away between adjacent sections. In this embodiment, wedge-shaped portions of the tube are cut away between adjacent sections to provide space (1420) to flex.

Adjacent pairs of living hinges (1415) are orientated at about 90 degrees from each other. For example, in FIG. 14, the pair of living hinges (1415 a) between adjacent sections (1412 a and 1412 b) are orientated at about 90 degrees from the pair of living hinges (1415 b) between adjacent sections (1412 a and 1412 b). The 90 degree orientation between adjacent pairs of living hinges (1415) enable the torque shaft (1400) to flex or bend in many directions.

The torque shaft further comprises a pair of torque keys (1430) between adjacent sections (1412 a, 1412 b, 1412 c, etc.). Each pair of torque keys (1430) extend from opposite sides of a section (1412 a, 1412 b, 1412 c, etc.) and is received in a pair of slots (1435) in an adjacent section (1412 a, 1412 b, 1412 c, etc). To allow adjacent sections (1412 a, 1412 b, 1412 c, etc.) to bend about the hinges (1415), the slots (1435) are dimensioned so that the corresponding torque keys (1430) can slide in the slots (1435) to allow flexing, bending, or pivoting. The torque keys (1430) transmit torque between adjacent sections (1412 a, 1412 b, 1412 c, etc.) of the shaft when the shaft is rotated about its longitudinal axis by pushing against the side walls of the corresponding slots (1435). The torque keys (1430) may be contiguous with the sections (1412 a, 1412 b, 1412 c, etc.) or may be made of separate pieces attached to the sections (1412 a, 1412 b, 1412 c, etc.).

FIGS. 15-16 show two views of two torque shafts (1502 and 1504) with one of the torque shafts (1504) disposed within the other torque shaft (1502). As explained above, a torque shaft has to be rotated by a certain amount at one end before torque may be transmitted to the other end of the shaft. This amount of rotation is referred to as wind-up. In this example, the two torque shafts (1502 and 1504) may be operated to provide opposing torque as indicated by the arrows in the FIGS. 15 and 16. Since the two torque shafts (1502 and 1504) provide torque or rotation in oppose directions, each torque shaft may be pre-wound or pre-loaded to remove wind-up before use. In FIG. 15, the outer torque shaft (1502) may be pre-wound in the counter clockwise direction and the inner torque shaft (1504) may be pre-wound in the clockwise direction as indicated by arrows. The torque shafts (1502 and 1504) may be pre-wound until the wind-up slack is removed from each of the two shafts (1502 and 1504). When the torque shafts (1502 and 1504) are pre-wound, the outer torque shaft (1502) may tendency to unravel in the clockwise direction and the inner torque shaft (1504) may have a tendency to unravel in the counter clockwise direction. To prevent the torque shafts (1502 and 1504) from unraveling after they are pre-wound, an interlocking feature may be placed between the two torque shafts.

FIG. 16 shows an example of a pin (1525) connected to the inner torque shaft (1504) and received in a slot (1530) in the outer torque shaft (1502). The pin (1525) engages an end surface of slot (1530), which prevents the two torque shafts (1502 and 15204) from unraveling. The slot (1530) runs along part of the circumference of the outer shaft (1502) to allow the ends of the torque shafts (1502 and 1504) to be rotated in opposing direction.

FIG. 17 shows an exploded and a perspective view of an example of pull-pull torque drive (1700) according to an embodiment. The torque drive (1700) comprises a slotted tube (1710), a cable drum hub (1720), and a sheave (1730). The drum hub (1720) is placed in the tube (1710) and rotates on the sheave (1730). The torque drive (1700) further comprises two cables (1735) running through coil pipes (1750) (only one of the cables is shown in FIG. 17). The cables (1735) are threaded through channels (1740) in the sheave (1730) and wound around the drum hub (1720) in different directions. The end of each cable (1735) is attached to the drum hub (1720). FIG. 17 shows one of the cables (1735) wound around the hub (1720) in one direction. The other cable (not shown) is wound around the hub (1720) in the opposite direction.

The cables (1735) enable the cable drum hub (1720) to be rotated in either direction with respect to the tube (1710) by pulling one of the cables (1735) axially. Pulling on one of the cables (1735) causes that one of the cables (1735) to unwind around the hub (1720); thereby, rotating the hub (1720). This also causes the other cable (1735) to wind around the hub (1720) so that the hub (1720) can be rotated in the other direction by pulling the other cable (1735).

The pull-pull torque drive (1700) is useful for deploying a prosthetic heart valve in a patient, which is described in more detail in application Ser. No. 11/066,126, filed on Sep. 15, 2005.

FIG. 18 shows a device (1800) for translating axial movement of the shaft (1825) into rotational movement of the shaft (1810). This may be used for transmitting torque to the distal end of the shaft by applying axial force to the proximal end of the shaft. The device (1800) comprises a cylindrical sleeve (1810) with a curved slot (1820) and a pin (1815) connected to the shaft (1825) that slides in the slot (1820). When axial force is applied to the shaft (1825), the pin (1815) connected to the shaft travels along the curved slot (1820) of the sleeve (1810) causing the sleeve (1810) to rotate.

FIG. 19A illustrates an elongate flexible torque instrument (100) being used to deliver an implant to a target site inside a patient in accordance with one embodiment of the present invention. The process of using the elongate flexible torque instrument (100) to deliver and deploy an implant is illustrated in process flowchart of FIG. 19B. The process starts by inserting a distal portion of an elongate flexible torque instrument into a patient, in step (1910). Typically, the insertion is made through either a natural body opening or small incision. As illustrated in FIG. 19A, a small incision is made near the femoral vessel and the distal portion of the elongate flexible torque instrument (100) is advanced and navigated through the vasculature of the patient, in step (1920). In this example, the distal portion of the elongate flexible torque instrument (100) may be advanced and navigated up to the inferior vena cava and into the right ventricle of the patient's heart. The distal portion of the elongate flexible torque instrument (100) is further advanced through the septum and into the left ventricle of the heart. From there, the distal portion of the elongate flexible torque instrument is navigated down, approximately 90 degrees or more, and through the mitral valve and into the left atrium, as illustrated in FIG. 19C. Throughout this procedure the elongate body (102) may be required to be steered or navigated in various directions and the torque members of the elongate body (102) may be flexed, bent, and/or pivoted in order to accommodate the movement of the elongate body (102) through various tortuous pathways of the vasculature. In addition, the elongate body (102) and the flexible torque members may be flexed, bent, and/or pivoted into various complex shapes and tight curvatures. As further illustrated in FIG. 19C, the distal portion of the elongate flexible torque instrument (100) is further navigated and advanced up the aortic arch, which may require a significant tight turn, approximately 180 degrees, and the distal portion of the flexible torque instrument may be bent into a tight “J” shaped curvature. That is, the distal portion of the elongate flexible instrument may be bent in a way that is double-back forward itself type of configuration. As previously discussed, the segment members of the flexible torque member are particularly configured to allow such flexibility for the elongate body to form complex shapes and tight curvatures. As the distal portion of the elongate flexible torque instrument (100) is navigated into position, torque is applied at the proximal portion and transmitted to the distal portion of the elongate flexible instrument to operate an implant deployment apparatus (112), in step (1930). In this example, the transmitted torque operates an implant deployment apparatus (112) and an implant is deployed from the deployment apparatus (112) to a location at or near the aortic root, in step (1940). This procedure in delivering an implant may be known as the antegrade approach. Alternatively, a retrograde approach may also be used to deliver an implant, as illustrated in FIG. 19D. In this procedure, similar to the process described in the flowchart of FIG. 19B. The process starts by inserting a distal portion of an elongate flexible torque instrument (100) into a patient. Typically, the insertion is made through either a natural body opening or small incision. In the example illustrated in FIG. 19A, a small incision is made near the femoral vessel and the distal portion of the elongate flexible torque instrument (100) is advanced and navigated through the vasculature of the patient. In the retrograde approach, the distal portion of the elongate flexible torque instrument is navigated from the femoral vessel through the vasculature to the aortic arch. Throughout this procedure the elongate body (102) may be required to be steer or navigated to various directions and the torque members of the elongate body (102) may be flexed, bent, and/or pivoted in order to accommodate the movement of the elongate body (102) through various tortuous pathways of the vasculature. The distal portion of the elongate flexible torque instrument (100) is navigated in to position at or near the aortic valve by way of the aortic arch, and then torque may be applied at the proximal portion and transmitted to the distal portion of the elongate flexible instrument to operate an implant deployment apparatus (112). In this example, the transmitted torque operates an implant deployment apparatus (112) and an implant is deployed from the deployment apparatus (112) to a location at or near the aortic root.

While the specification describes particular embodiments of the present inventive subject matter, those of ordinary skill in the art having the benefit of this disclosure can devise variations of the subject matter without departing from the inventive concepts. In addition, the previous description is provided to enable a person of ordinary skill in the art to practice the various embodiments described herein. Various modifications to these embodiments will be readily apparent to those of ordinary skill in the art, and the generic principles defined herein may be applied to other embodiments. Thus, the claims are not intended to be limited to the embodiments shown herein, but are to be accorded the full scope consistent with the language of the claims, wherein reference to an element in the singular is not intended to mean “one and only one” unless specifically so stated, but rather “one or more.” All structural and functional equivalents to the elements of the various embodiments described throughout this disclosure that are known or later come to be known to those of ordinary skill in the art are expressly incorporated herein by reference and are intended to be encompassed by the claims. Moreover, nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claims. No claim element is to be construed under the provisions of 35 U.S.C. § 112, sixth paragraph, unless the element is expressly recited using the phrase “means for” or, in the case of a method claim, the element is recited using the phrase “step for.” 

1. An apparatus for transmission of torque, comprising: a plurality of segments coupled together in an elongate configuration, wherein each segment comprises: a first end comprising a male feature; and a second end comprising a female feature, the female feature having a shape corresponding to the male feature such that the female feature is configured to receive the male feature of the first end of an adjacent segment.
 2. The apparatus of claim 1, wherein the male feature has a “T” like shape.
 3. The apparatus of claim 1, wherein the male feature has a teardrop shape.
 4. The apparatus of claim 1, wherein the male feature is configured to interlock with the female feature.
 5. The apparatus of claim 1, wherein the male feature is a first male feature and the female feature is a first female feature, each segment comprising: a second male feature on the first end, the second male feature being configured differently from the first male feature; and a second female feature on the second end, the second female feature being configured differently from the first female feature, the second female feature having a shape corresponding to the second male feature such that the second female feature is configured to receive the second male feature of the first end of an adjacent rigid segment.
 6. The apparatus of claim 1, further comprising a segment having a second end that does not have a female feature.
 7. The apparatus of claim 1, further comprising a segment having a first end that does not have a male feature.
 8. The apparatus of claim 1, wherein a first segment of the plurality of segments is pivotable with respect to an adjacent second segment of the plurality of segments.
 9. The apparatus of claim 8, wherein the female feature of the second segment is configured to rotate about the male feature of the first segment.
 10. The apparatus of claim 9, wherein each segment comprises a pivot space, the pivot space is adjacent at least one of the male and female features, the female feature is a first female feature, the male feature is a first male feature, and the pivot space is a first pivot space, each segment further comprising: a second male feature located opposite the first male feature and having the same configuration as the first male feature; a second female feature located opposite the first female feature and having the same configuration as the first female feature; and a second pivot space located opposite the first pivot space and having the same configuration as the first pivot space.
 11. The apparatus of claim 8, wherein the first segment is coupled to the second segment by a hinge.
 12. The apparatus of claim 11, wherein the hinge is a living hinge, the male feature is configured to slide within the female feature, each segment further comprises a pivot space and at least one of the male or female features is located in at least one of the pivot spaces of the segments, and the living hinge is a first living hinge, the female feature is a first female feature, the male feature is a first male feature, and the pivot space is a first pivot space, each segment further comprising: a second living hinge located opposite the first living hinge and having a similar configuration to the first living hinge; a second male feature located opposite the first male feature and having a similar configuration to the first male feature; a second female feature located opposite the first female feature and having a similar configuration to the first female feature; and a second pivot space located opposite the first pivot space.
 13. A medical apparatus, comprising: a tubular member configured to interface with a prosthesis; a torque drive coupled with the tubular member and configured to rotate the tubular member, the torque drive being configured to fit within the vasculature of a patient.
 14. The medical apparatus of claim 13, wherein the tubular member is a torque shaft.
 15. The medical apparatus of claim 14, further comprising a cable configured to interface with the torque drive.
 16. The medical apparatus of claim 15, wherein the torque drive is configured to translate axial motion of the cable into rotational motion of the torque shaft, wherein the torque shaft comprises: a sheave; and a cable hub rotatably coupled to the sheave and fixably coupled with the torque shaft, the cable hub configured to receive the cable in a wrapped state.
 17. An elongate flexible torque instrument for deploying implants, comprising: an elongate body comprising a plurality of flexible torque members, wherein each torque member is comprised of segments, the segments being configured to pivot with respect to an adjacent segment, and each torque member is configured to transmit torque from a proximal portion to a distal portion of the torque member; a handle operatively coupled to the proximal end of each of the flexible torque members; wherein the handle comprises a control lever configured to operate one or more control wires to steer the elongate flexible body and a plurality of control knobs configured to apply torque to the flexible torque members to transmit torque from proximal portions of the flexible torque members to distal portions of the flexible torque members; and an implant deployment apparatus operatively coupled to the distal ends of the flexible torque members, wherein the implant deployment apparatus is configured to deploy an implant with torque transmitted to the flexible torque members.
 18. The elongate flexible torque instrument of claim 17, wherein each segment is coupled to an adjacent segment by a link element.
 19. The elongate flexible torque instrument of claim 17, wherein the segments are pivoted about a link element.
 20. The elongate flexible torque instrument of claim 18, wherein the link element is a physical link element, a pivotal link element, or a torque link element.
 21. The elongate flexible torque instrument of claim 17, wherein each segment is coupled to an adjacent segment by a combination of a physical link element and a torque link element or a pivotal link element and a torque link element.
 22. The elongate flexible torque instrument of claim 21, wherein the physical link element is disposed about 90 degrees from the torque link element or the pivotal link element is disposed about 90 degrees from the torque link element.
 23. The elongate flexible torque instrument of claim 17, wherein the flexible torque members are configured to apply counter-acting torque, counter-rotating, or opposing torque to the implant deployment apparatus to deploy an implant.
 24. The elongate flexible torque instrument of claim 20, wherein the physical link element comprises one or more struts and one or more spaces between the one or more struts.
 25. The elongate flexible torque instrument of claim 20, wherein the torque link element comprises a male element and a female element, and wherein the female element of one segment is configured to receive the male element of an adjacent segment.
 26. The elongate flexible torque instrument of claim 17, wherein the segment are cut at an angle in the range between about 0 degree and about 90 degrees.
 27. The elongate flexible torque instrument of claim 17, wherein the flexible torque member includes a flexible membrane sheath to maintain the segments together.
 28. A method for deploying an implant inside a body of a patient, comprising: inserting a distal portion of an elongate flexible torque instrument into a patient, the elongate flexible torque instrument comprising a plurality of flexible torque members, each flexible torque member comprising a plurality of segments; advancing and navigating the distal portion of the elongate flexible torque instrument through natural pathways inside the patient to a target site; applying torque to a proximal portion of the elongate flexible torque instrument; and transmitting the applied torque from the proximal portion to the distal portion of the elongate flexible torque instrument to operate an implant deployment apparatus, wherein the transmitted torque facilitates deployment of an implant from the implant deployment apparatus to the target site.
 29. The method for deploying an implant inside a body of a patient of claim 28, wherein counter-acting torque, counter-rotating torque, or opposing torque is applied to operate the implant deployment apparatus.
 30. An apparatus for transmitting torque, comprising: an elongate body, the elongate body comprising a plurality of segments, each segment configured to pivot with respect to an adjacent segment and being further configured to have a pair of link elements, each link element having a hub and a plurality of physical link elements extending from said hub and coupled with a rim of an adjacent segment. 